1 files changed, 127 insertions, 0 deletions
diff --git a/src/runtime/dotNet/NativeGU.cs b/src/runtime/dotNet/NativeGU.cs
new file mode 100644
index 000000000..2e7f11c0d
--- /dev/null
+++ b/src/runtime/dotNet/NativeGU.cs
@@ -0,0 +1,127 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Runtime.InteropServices;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace PGFSharp
+{
+    internal static class NativeGU
+    {
+
+        const string LIBNAME = "gu.dll";
+        const CallingConvention CC = CallingConvention.Cdecl;
+
+        [DllImport(LIBNAME, CallingConvention = CC)]
+        public static extern IntPtr gu_new_pool();
+
+        [DllImport(LIBNAME, CallingConvention = CC)]
+        public static extern IntPtr gu_new_exn(IntPtr pool);
+
+        [DllImport(LIBNAME, CallingConvention = CC)]
+        public static extern void gu_pool_free(IntPtr pool);
+
+        [DllImport(LIBNAME, CallingConvention = CC)]
+        public static extern IntPtr get_gu_null_variant();
+
+        [DllImport(LIBNAME, CallingConvention = CC)]
+        public static extern IntPtr gu_string_buf_out(IntPtr sbuf);
+
+        [DllImport(LIBNAME, CallingConvention = CC)]
+        public static extern IntPtr gu_new_string_buf(IntPtr pool);
+
+        [DllImport(LIBNAME, CallingConvention = CC)]
+        public static extern IntPtr gu_data_in(IntPtr str, int len, IntPtr pool);
+
+        [DllImport(LIBNAME, CallingConvention = CC)]
+        public static extern IntPtr gu_string_buf_freeze(IntPtr sbuf, IntPtr pool);
+
+        [DllImport(LIBNAME, CallingConvention = CC)]
+        [return: MarshalAs(UnmanagedType.I1)]
+        public static extern bool gu_exn_is_raised(IntPtr err);
+
+        [DllImport(LIBNAME, CallingConvention = CC)]
+        public static extern void gu_enum_next(IntPtr enum_, ref IntPtr outPtr, IntPtr pool);
+
+        [DllImport(LIBNAME, CallingConvention = CC)]
+        public static extern GuVariantInfo gu_variant_open(IntPtr variant);
+
+        [DllImport(LIBNAME, CallingConvention = CC)]
+        public static extern IntPtr gu_alloc_variant(byte tag, UIntPtr size, UIntPtr align, ref IntPtr out_, IntPtr pool);
+
+        [DllImport(LIBNAME, CallingConvention = CC)]
+        public static extern IntPtr gu_make_variant(byte tag, UIntPtr size, UIntPtr align, ref IntPtr init, IntPtr pool);
+
+        [StructLayout(LayoutKind.Sequential)]
+        public struct GuVariantInfo
+        {
+            public int Tag;
+            public IntPtr Data;
+        }
+
+
+        [StructLayout(LayoutKind.Sequential)]
+        public struct GuSeq
+        {
+            public UIntPtr length;
+        }
+
+        public static uint SeqLength(IntPtr seqptr)
+        {
+            var seq = Marshal.PtrToStructure<GuSeq>(seqptr);
+            return (uint)seq.length;
+        }
+
+        public static T gu_seq_index<T>(IntPtr seq, int index)
+        {
+            var dataPtr = seq + Marshal.SizeOf<GuSeq>();
+            var hypoPtr = dataPtr + index * Marshal.SizeOf<T>();
+            var hypo = Marshal.PtrToStructure<T>(hypoPtr);
+            return hypo;
+        }
+
+        public class NativeMemoryPool
+        {
+            private IntPtr _ptr;
+            internal IntPtr Ptr => _ptr;
+
+            public NativeMemoryPool()
+            {
+                _ptr = gu_new_pool();
+                if (_ptr == IntPtr.Zero) throw new Exception();
+            }
+
+            ~NativeMemoryPool()
+            {
+                gu_pool_free(_ptr);
+                _ptr = IntPtr.Zero;
+            }
+        }
+
+        public class NativeExceptionContext
+        {
+            private IntPtr _ptr;
+            internal IntPtr Ptr => _ptr;
+
+            public NativeExceptionContext(NativeMemoryPool pool)
+            {
+                _ptr = gu_new_exn(pool.Ptr);
+                if (_ptr == IntPtr.Zero) throw new Exception();
+            }
+
+            public bool IsRaised => gu_exn_is_raised(_ptr);
+        }
+
+        public static IEnumerable<IntPtr> IteratorToIEnumerable(IntPtr iterator, IntPtr pool)
+        {
+            IntPtr ptr = IntPtr.Zero;
+            NativeGU.gu_enum_next(iterator, ref ptr, pool);
+            while (ptr != IntPtr.Zero)
+            {
+                yield return ptr;
+                NativeGU.gu_enum_next(iterator, ref ptr, pool);
+            }
+        }
+    }
+}